1. Field of Invention
The present invention relates to an effort-saving stapler.
2. Related Prior Art
As disclosed in Taiwanese Patent Publication No. 576290, a conventional stapler 10 includes a shell 20 and a mechanism 30. The shell 20 includes two halves. The mechanism 30 includes a hammer 31, a leaf spring 32 and a trigger 33. The hammer 31 is movably disposed in the shell 20. The leaf spring 32 is disposed in the shell 20. The leaf spring 32 is connected to the hammer 31. The trigger 33 is connected to the shell 20 by a pin 34. A tongue 35 is connected to the trigger 33 by a pin 37. The tongue 35 is biased by a torque spring 36. The tongue 35 is normally inserted in an aperture 311 defined in the hammer 31. To staple, a user pulls the trigger 33. The tongue 35 lifts the hammer 31 that loads the leaf spring 32. Having fully pulled the trigger 33, the user causes the tongue 35 to leave the hammer 31. The leaf spring 32 drives the hammer 31 down to hit the nail. The use, however, has to pull the trigger 33 harder and harder. The user has to pull the trigger 33 hard so that he soon feels tired.
The present invention is therefore intended to obviate or at least alleviate the problems encountered in the prior art.